Understanding design
Pioneer motorcycle builders were off to a running start developing their models, as experience of cycle design helped them with steering head angles, length between axles and needed rigidity. But adding the weight of an engine, filled fuel tank, the lengthening of frames to accommodate pedalling gear and later gearboxes meant the cycle design was a good starting point, but wasn’t the ideal.
An example of design problems lives in our workshop. About 15 years ago, son Peter bought a totally dismantled 1910 499cc Campion-JAP. It proved the easiest restoration we’ve undertaken, with Peter finishing it in seven months, from five boxes of parts. Although dismantled for 35 years, the largest missing item was a fork spring. With ongoing leg injury problems, I put my 2023 Pioneer Run helmet on the Campion, because it has a clutch, which saves me many pedal or run and jump starts on route to Brighton. It made sense – but riding it needs some thought.
Peter’s Campion is amongst the first machines made by the respected bicycle maker, the Campion Cycle Co Ltd, Robin Hood Street, Nottingham, who built their first models circa 1908/9. The Campion is flawed, in that it carries its engine far too low and its steering head angle is too steep. With less than 2½inches (62mm) ground clearance under its precious cast aluminium crankcases, one watches the road continually for bumps and potholes, with traffic calming humps a real menace.
Campion and others with similarly low-slung engines soon resolved the problem and before the
